Ever since satellites and other payloads were sent into space, i.e. making more than one complete orbit around the Earth, the method and means for launching these payloads were by use of rockets, particularly multi-stage rockets. Rockets themselves have a long history and their governing principles were well formulated by the time space launches were actually undertaken. See for example Frank J. Malina et al--Journal of the Aeronautical Sciences, Aug. 1947, pages 471-480; Howard S. Seifert et al-American Journal of Physics, volume 15, 1947, pages 255-266; and Richard D. Geckler-ARS Journal, June 1960, pages 531-536. These references and others discuss the principles of multi-stage rockets for space launches and conclude that the optimum arrangement of the various stages of a multi-stage rocket is when the payload ratio is equal for all the stages. This payload ratio is defined for each stage as the ratio of the mass of the carried load or payload to the mass of the rocket at the moment when that stage begins to fire. Thus, for example, in a three-stage rocket with a 100 kg. payload, which is carried in the body of the third stage, the third stage would have a gross mass, including the payload, of about 500 kg. The payload ratio of the third stage is thus 100/500 or 0.2. The third stage is of course launched in flight from the second stage, the gross mass of which including the third stage and payload is 2,500 kg., again giving a payload ratio of 500/3,500 which equals 0.2. The gross mass of the first stage, which is really the entire rocket assembly, is 12,500 kg. and therefore the mass of the second stage is 0.2 of the total mass. In other words, for every weight unit of the space payload, one requires about four weights of the third stage rocket (the stage closest to the payload at the time of launching), about 20 weight units of the middle stage, and about 100 weight units of the lower stage, which is ignited first at the time of launching.
The prior art weight relationship, which was considered optimal, between the various stages of the rocket, is calculated to provide a maximum total velocity at the end of firing all the stages. According to this stage arrangement, the first stage rocket is the heaviest and the weight of each subsequent stage radically decreases. It was calculated that the lower stage rocket must be at least two and one half (2.5) the weight of the stage above it. This makes the development, production and launching of these rockets quite expensive. It has up to now been the conventional theory that a favourable combination of circumstances for space launches is obtained when the payload ratio lies between 0.2 and 0.4.
In other words, when the ratio of the weights of the lower stage to the stages above it lies between 2.5 and 5. To the best of our knowledge, these payload ratios are used today for practically all space launches. According to this prior art, it is mathematically inconsistent to have the lower two rocket stages be equal in weight.
When one takes into consideration the costs of engineering, development, production, maintenance and launching of such rockets, it can well be understood how important it is to be able to reduce the size and weight of each stage of the rocket for maximum efficiency and cost saving.